How are you trying to upload the zip
In advance try this:
Download the data pack. It should be a .zip file or directory.
Open your server folder, then open the folder of the world you wish to install the datapack in (default: world).
Create and put the data pack into a folder named datapacks into the world folder
Restart the server
If the data pack has a correct format, it would be enabled on the server. You can verify by typing /datapack list enabled from the consolend find an entry named [file/your data pack file/directory name].
Also in the future if you need help with anything please put it into the help discussion and it will be answered much faster